Galaxy Tab S stuck in bootloop

Galaxy Tab S 10.5 SM-T800 stuck in a bootloop with the TWRP logo on the screen. I can not get the tablet to go into download mode. I have tried all of the different methods to enter download mode, i.e. Power & Vol - & Home, Drain the battery > Plug into PC while holding Vol - & Home, Power & Vol + & Vol -. None of these combinations do anything. The only thing I can do to get a response is to press Power & Vol +, which reboots the device right back into the TWRP loop after the Samsung Logo.

The device is seen by Windows with the Samsung Drivers but is not mounted to a drive letter, and I can not mount it.

ADB and fastboot do not see the device.

I would like to flash a new rom either custom or stock, but I need to be able to get the device into download mode so it can be seen by odin.